岡山医学会Acta Medica Okayama0030-15587061958結核菌の薬剤耐性に関する研究 第3編 INAH耐性菌, 二重耐性菌の毒力及びINAH耐性菌のCatalase活性特に毒力との関係に関する研究19231938ENTojiroKageyamaBy comparing the virulence of INAH-resistant bacilli obtained in one-step selection and that of the INAH-resistant bacilli stocked in our laboratory, and also by studying the virulence of the INAH-and SM-double-resistant bacilli and the relationship between the catalase activity and the virulence of INAH-resistant bacilli, the author obtained the following results. 1) In the experiment with guinea pigs both the INAH-resistant bacilli obtained by one-step selection and the stock INAH-resistant bacilli proved to not so virulent. 2) The virulence of double resistant bacilli grow weaker when SM-resistant bacilli acquired INAH-resistance, and that of INAH-resistant bacilli remain weakly virulent even when they acquired SM-resistance. 3) On examining catalase activity and the degree of INAH-resistance, on the whole bacilli become catalase-negative as their resistance increases, but some remain catalase positive even when their resistance is high. Therefore, the relationship between INAH-resistance and catalase activity is not absolute. 4) When catalase negative 10 γ-resistant strain is cultured successively in a modified medium, it turns catalase positive. Moreover, it has been proven that catalase negative strain turns to catalase positive due to peculiar conditions of the medium but not due to the decrease in resistance, because even when 10 γ/cc. of INAH is added to the modified medium, bacilli turn to catalase positive just the same. 5) In the study of the relationship between catalase activity and virulence to guinea pigs, it has been found that the virulence of catalase-negative l0 γ-resistant strain is weakened. Even in the case of l0 γ-resistant bacilli which are catalase positive (such as obtained from patient or isolated in a modified medium), their virulence is maintained. In the case of INAH-resistant strain if they are catalase positive, the virulence of the bacilli is maintained in a fair degree. Consequently, it is possible to regain the virulence artificially to a certain extent by changing catalase to positive in a modified medium. Furthermore, in the case of the bacilli isolated in a modified medium and possessing the same degree of catalase positive activity, the virulence proved to be higher when the resistance is decreased. This fact seems to indicate that the virulence of INAH-resistant bacilli is in a way correlated to the resistance irrespective of catalase. 6) The relationship between catalase activity and the virulence to mice can not be detected so clearly as in the case of guinea pigs.No potential conflict of interest relevant to this article was reported.岡山医学会Acta Medica Okayama0030-15587061958結核菌の薬剤耐性に関する研究 第2編 結核菌の二重耐性に関する研究19111921ENTojiroKageyamaThe author performed both in vitro and in vivo experiments of double resistant tubercle bacilli with the purpose to determine whether SM or INAH should be used at first to obtain a better result. As the result the following findings were obtained. 1) With the use of H(37)Rv parent strain, SM-resistant H(37)Rv-strain, resistance increment experiments were performed in Kirchner's serum liquid media. In the successive cultures by the tenth successive culture both H(37)Rv parent strain and SM-resistant strain attained the resistance against INAH up to 100 γ/cc., while the parent strain and INAH-resistant strain acquired the resistance against SM up to 10,000 γ/cc. by the tenth successive culture. In other words, in the acquiring of resistance there is a significant difference between SM and INAH. 2) In comparing the resistance increment during ten successive cultures, SM-resistant strain acquired the resistance against INAH later than the parent strain. INAH-resstant strain likewise was slower in acquiring the resistance against SM than the parent strain. Because no difference can be found between the two in vitro experiments, it can not be said that clinically INAH should be better used prior to the use of SM. 3) In the experimental tuberculosis of mice, a fairly high resistance has been acquired by SM injection or INAH injection. 4) In the experiments with mice, the acquiring of resistance against SM in the cases inoculated with INAH-resistant strain is extremely slower than the acquiring of resistanec against INAH in the cases inoculated with SM-resistant strain. Therefore, judging from the experiments with mice, it may be said that clinically INAH would be better used first.No potential conflict of interest relevant to this article was reported.岡山医学会Acta Medica Okayama0030-15587061958結核菌の薬剤耐性に関する研究 第1編 薬剤耐性結核菌の復帰に関する研究18971909ENTojiroKageyamaWith a view to elucidate the mechanism of reversibility of resistant tubercle bacilli, the author has performed in vitro experiments of resistance reversibility by observing changes occurring in successive culture of resistant bacilli together with different antituberculous agents, the filtrate of sensitive strain or dead bacilli, by changing ingredients of successive media; and also by injecting different kinds of antituberculous agents into imice the rever sibility in vivo has been studied. As the result the following interesting data were obtained. 1) In the successive cultures of SM-resistant H(37)Rv-strain and INAH-resistant-H(37)Rv-strain in the medium of Kirchner's albumin or serum liquid medium, each loaded with PAS, Viomycin, Pyrazinamide, INAH or SM, no reversibility of resistance could be recognized. 2) In the successive cultures of SM-resistant H(37)Rv-strain and SM-resistant avian type Takeo strain in the medium loaded with the filtrate of sensitive parent strain or dead bacilli, no reversibility of resistance could be observed. 3) In the cases of successive cultures of SM-resistant-H(37)Rv-strain and INAH-resistant-H(37)Rv-strain in modified media of 1% Ogawa's medium, SM-resistant bacilli revealed no resistance-reversibility in any of these media. INAH-resistant strain successively cultured in the medium containing solely KH(2)PO(4) or only sodium glutamate, they began to show a diminution in resistance about the fifth generation. As for the mechanism of this diminution in resistance it is possible to assume an induced backmutation in modified media. 4) In the experiments with mice, the diminution in resistance has been observed in the cases inoculated with SM-resistant strain and injected with INAH as well as in the cases inoculated with INAH resistant strain and injected with SM. It is assumed that the susceptibility of resistant bacilli to other agents is elevated in vivo.No potential conflict of interest relevant to this article was reported.